Merciless Resolve (Grim Focus) light attacks don't stack in non-CP Cyrodiil?

Reivax

I probably never go to non-CP Cyrodiil, but with event being on, I wanted to play and it was only instanc I could squeeze in on
I noticed that the light/heavy attack stacks won't accumulate across enemies.

Usually you do 5 light/heavy hits, it shows the number increase until 5, then sit there until you fire the spectral arrow.
But in the non-CP instance, the 5 would reset after death of enemy you light-attacked to increase the number

Is this normal? I don't know what CP has to do with that ability, but that's only difference I can see. The functionality of the attack works normal everywhere else for me.

xNepo

Happens even in cp-imperial/cyrodiil. I do not know if it is a bug. I sent a report on it, awaiting reply.